欧西坦尼亚（奥克语：Occitània utsiˈtanjɔ ，有时作 lo País d'Òc，即“奥克郡”），是欧洲南部的一个地区，历史上以奥克语为主要语言，并且现今仍时有使用这种语言，或在多数地方作为第二语言。这个文化区域大致包括了法国南部、摩纳哥、意大利的局部（奥克谷、Guardia Piemontese）以及西班牙的小部分（阿兰谷）。欧西坦尼亚自中世纪以来作为一个语言学以及文化概念得予认同，但未曾有法律或政治实体以这个名字创建，尽管这块疆土在罗马时期作为七省以及中世纪早期作为阿基坦尼亚（或作图卢兹的西哥特王国）曾获统一。

Occitania (Occitan:Occitània, IPA: [uksiˈtanjɔ], [ukʃiˈtanjɔ], [usiˈtanjɔ], [uksiˈtanja] or [utsiˈtanjɔ]), also sometimes lo País d'Òc, "the Oc Country"), is the historical region in southern Europe where Occitan was historically the main language spoken, and where it is sometimes still used, for the most part as a second language. This cultural area roughly encompasses the southern half of France, as well as Monaco and smaller parts of Italy (Occitan Valleys, Guardia Piemontese) and Spain (Aran Valley). Occitania has been recognized as a linguistic and cultural concept since the Middle Ages, but has never been a legal nor a political entity under this name, although the territory was united in Roman times as the Seven Provinces (Latin:Septem Provinciæ) and in the early Middle Ages (Aquitanica or the Visigothic Kingdom of Toulouse) before the French conquest started in the early 13th century.